public DeleteAttachmentCommandValidator(
IInvitationValidator invitationValidator,
IRowVersionValidator rowVersionValidator)
{
CascadeMode = CascadeMode.Stop;
RuleFor(command => command)
.MustAsync((command, cancellationToken) => BeAnExistingInvitationAsync(command.InvitationId, cancellationToken))
.WithMessage(command => $"Invitation with this ID does not exist! Id={command.InvitationId}")
.MustAsync((command, cancellationToken) => BeAnExistingAttachmentAsync(command.InvitationId, command.AttachmentId, cancellationToken))
.WithMessage(command => $"Attachment doesn't exist! Attachment={command.AttachmentId}.")
.Must(command => HaveAValidRowVersion(command.RowVersion))
.WithMessage(command => $"Not a valid row version! Row version={command.RowVersion}.");
async Task <bool> BeAnExistingInvitationAsync(int invitationId, CancellationToken cancellationToken)
=> await invitationValidator.IpoExistsAsync(invitationId, cancellationToken);
async Task <bool> BeAnExistingAttachmentAsync(int invitationId, int attachmentId, CancellationToken cancellationToken)
=> await invitationValidator.AttachmentExistsAsync(invitationId, attachmentId, cancellationToken);
bool HaveAValidRowVersion(string rowVersion)
=> rowVersionValidator.IsValid(rowVersion);
}